aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/math-emu/math.c
blob: 5891534727617836c6ebfffdb958f95edf12c107 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
/*
 * Copyright (C) 1999  Eddie C. Dost  (ecd@atecom.com)
 */

#include <linux/config.h>
#include <linux/types.h>
#include <linux/sched.h>

#include <asm/uaccess.h>
#include <asm/reg.h>

#include "sfp-machine.h"
#include "double.h"

#define FLOATFUNC(x)	extern int x(void *, void *, void *, void *)

FLOATFUNC(fadd);
FLOATFUNC(fadds);
FLOATFUNC(fdiv);
FLOATFUNC(fdivs);
FLOATFUNC(fmul);
FLOATFUNC(fmuls);
FLOATFUNC(fsub);
FLOATFUNC(fsubs);

FLOATFUNC(fmadd);
FLOATFUNC(fmadds);
FLOATFUNC(fmsub);
FLOATFUNC(fmsubs);
FLOATFUNC(fnmadd);
FLOATFUNC(fnmadds);
FLOATFUNC(fnmsub);
FLOATFUNC(fnmsubs);

FLOATFUNC(fctiw);
FLOATFUNC(fctiwz);
FLOATFUNC(frsp);

FLOATFUNC(fcmpo);
FLOATFUNC(fcmpu);

FLOATFUNC(mcrfs);
FLOATFUNC(mffs);
FLOATFUNC(mtfsb0);
FLOATFUNC(mtfsb1);
FLOATFUNC(mtfsf);
FLOATFUNC(mtfsfi);

FLOATFUNC(lfd);
FLOATFUNC(lfs);

FLOATFUNC(stfd);
FLOATFUNC(stfs);
FLOATFUNC(stfiwx);

FLOATFUNC(fabs);
FLOATFUNC(fmr);
FLOATFUNC(fnabs);
FLOATFUNC(fneg);

/* Optional */
FLOATFUNC(fres);
FLOATFUNC(frsqrte);
FLOATFUNC(fsel);
FLOATFUNC(fsqrt);
FLOATFUNC(fsqrts);


#define OP31		0x1f		/*   31 */
#define LFS		0x30		/*   48 */
#define LFSU		0x31		/*   49 */
#define LFD		0x32		/*   50 */
#define LFDU		0x33		/*   51 */
#define STFS		0x34		/*   52 */
#define STFSU		0x35		/*   53 */
#define STFD		0x36		/*   54 */
#define STFDU		0x37		/*   55 */
#define OP59		0x3b		/*   59 */
#define OP63		0x3f		/*   63 */

/* Opcode 31: */
/* X-Form: */
#define LFSX		0x217		/*  535 */
#define LFSUX		0x237		/*  567 */
#define LFDX		0x257		/*  599 */
#define LFDUX		0x277		/*  631 */
#define STFSX		0x297		/*  663 */
#define STFSUX		0x2b7		/*  695 */
#define STFDX		0x2d7		/*  727 */
#define STFDUX		0x2f7		/*  759 */
#define STFIWX		0x3d7		/*  983 */

/* Opcode 59: */
/* A-Form: */
#define FDIVS		0x012		/*   18 */
#define FSUBS		0x014		/*   20 */
#define FADDS		0x015		/*   21 */
#define FSQRTS		0x016		/*   22 */
#define FRES		0x018		/*   24 */
#define FMULS		0x019		/*   25 */
#define FMSUBS		0x01c		/*   28 */
#define FMADDS		0x01d		/*   29 */
#define FNMSUBS		0x01e		/*   30 */
#define FNMADDS		0x01f		/*   31 */

/* Opcode 63: */
/* A-Form: */
#define FDIV		0x012		/*   18 */
#define FSUB		0x014		/*   20 */
#define FADD		0x015		/*   21 */
#define FSQRT		0x016		/*   22 */
#define FSEL		0x017		/*   23 */
#define FMUL		0x019		/*   25 */
#define FRSQRTE		0x01a		/*   26 */
#define FMSUB		0x01c		/*   28 */
#define FMADD		0x01d		/*   29 */
#define FNMSUB		0x01e		/*   30 */
#define FNMADD		0x01f		/*   31 */

/* X-Form: */
#define FCMPU		0x000		/*    0	*/
#define FRSP		0x00c		/*   12 */
#define FCTIW		0x00e		/*   14 */
#define FCTIWZ		0x00f		/*   15 */
#define FCMPO		0x020		/*   32 */
#define MTFSB1		0x026		/*   38 */
#define FNEG		0x028		/*   40 */
#define MCRFS		0x040		/*   64 */
#define MTFSB0		0x046		/*   70 */
#define FMR		0x048		/*   72 */
#define MTFSFI		0x086		/*  134 */
#define FNABS		0x088		/*  136 */
#define FABS		0x108		/*  264 */
#define MFFS		0x247		/*  583 */
#define MTFSF		0x2c7		/*  711 */


#define AB	2
#define AC	3
#define ABC	4
#define D	5
#define DU	6
#define X	7
#define XA	8
#define XB	9
#define XCR	11
#define XCRB	12
#define XCRI	13
#define XCRL	16
#define XE	14
#define XEU	15
#define XFLB	10

#ifdef CONFIG_MATH_EMULATION
static int
record_exception(struct pt_regs *regs, int eflag)
{
	u32 fpscr;

	fpscr = __FPU_FPSCR;

	if (eflag) {
		fpscr |= FPSCR_FX;
		if (eflag & EFLAG_OVERFLOW)
			fpscr |= FPSCR_OX;
		if (eflag & EFLAG_UNDERFLOW)
			fpscr |= FPSCR_UX;
		if (eflag & EFLAG_DIVZERO)
			fpscr |= FPSCR_ZX;
		if (eflag & EFLAG_INEXACT)
			fpscr |= FPSCR_XX;
		if (eflag & EFLAG_VXSNAN)
			fpscr |= FPSCR_VXSNAN;
		if (eflag & EFLAG_VXISI)
			fpscr |= FPSCR_VXISI;
		if (eflag & EFLAG_VXIDI)
			fpscr |= FPSCR_VXIDI;
		if (eflag & EFLAG_VXZDZ)
			fpscr |= FPSCR_VXZDZ;
		if (eflag & EFLAG_VXIMZ)
			fpscr |= FPSCR_VXIMZ;
		if (eflag & EFLAG_VXVC)
			fpscr |= FPSCR_VXVC;
		if (eflag & EFLAG_VXSOFT)
			fpscr |= FPSCR_VXSOFT;
		if (eflag & EFLAG_VXSQRT)
			fpscr |= FPSCR_VXSQRT;
		if (eflag & EFLAG_VXCVI)
			fpscr |= FPSCR_VXCVI;
	}

	fpscr &= ~(FPSCR_VX);
	if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
		     FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
		     FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
		fpscr |= FPSCR_VX;

	fpscr &= ~(FPSCR_FEX);
	if (((fpscr & FPSCR_VX) && (fpscr & FPSCR_VE)) ||
	    ((fpscr & FPSCR_OX) && (fpscr & FPSCR_OE)) ||
	    ((fpscr & FPSCR_UX) && (fpscr & FPSCR_UE)) ||
	    ((fpscr & FPSCR_ZX) && (fpscr & FPSCR_ZE)) ||
	    ((fpscr & FPSCR_XX) && (fpscr & FPSCR_XE)))
		fpscr |= FPSCR_FEX;

	__FPU_FPSCR = fpscr;

	return (fpscr & FPSCR_FEX) ? 1 : 0;
}
#endif /* CONFIG_MATH_EMULATION */

int
do_mathemu(struct pt_regs *regs)
{
	void *op0 = 0, *op1 = 0, *op2 = 0, *op3 = 0;
	unsigned long pc = regs->nip;
	signed short sdisp;
	u32 insn = 0;
	int idx = 0;
#ifdef CONFIG_MATH_EMULATION
	int (*func)(void *, void *, void *, void *);
	int type = 0;
	int eflag, trap;
#endif

	if (get_user(insn, (u32 *)pc))
		return -EFAULT;

#ifndef CONFIG_MATH_EMULATION
	switch (insn >> 26) {
	case LFD:
		idx = (insn >> 16) & 0x1f;
		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
		lfd(op0, op1, op2, op3);
		break;
	case LFDU:
		idx = (insn >> 16) & 0x1f;
		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
		lfd(op0, op1, op2, op3);
		regs->gpr[idx] = (unsigned long)op1;
		break;
	case STFD:
		idx = (insn >> 16) & 0x1f;
		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
		stfd(op0, op1, op2, op3);
		break;
	case STFDU:
		idx = (insn >> 16) & 0x1f;
		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
		stfd(op0, op1, op2, op3);
		regs->gpr[idx] = (unsigned long)op1;
		break;
	case OP63:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		fmr(op0, op1, op2, op3);
		break;
	default:
		goto illegal;
	}
#else /* CONFIG_MATH_EMULATION */
	switch (insn >> 26) {
	case LFS:	func = lfs;	type = D;	break;
	case LFSU:	func = lfs;	type = DU;	break;
	case LFD:	func = lfd;	type = D;	break;
	case LFDU:	func = lfd;	type = DU;	break;
	case STFS:	func = stfs;	type = D;	break;
	case STFSU:	func = stfs;	type = DU;	break;
	case STFD:	func = stfd;	type = D;	break;
	case STFDU:	func = stfd;	type = DU;	break;

	case OP31:
		switch ((insn >> 1) & 0x3ff) {
		case LFSX:	func = lfs;	type = XE;	break;
		case LFSUX:	func = lfs;	type = XEU;	break;
		case LFDX:	func = lfd;	type = XE;	break;
		case LFDUX:	func = lfd;	type = XEU;	break;
		case STFSX:	func = stfs;	type = XE;	break;
		case STFSUX:	func = stfs;	type = XEU;	break;
		case STFDX:	func = stfd;	type = XE;	break;
		case STFDUX:	func = stfd;	type = XEU;	break;
		case STFIWX:	func = stfiwx;	type = XE;	break;
		default:
			goto illegal;
		}
		break;

	case OP59:
		switch ((insn >> 1) & 0x1f) {
		case FDIVS:	func = fdivs;	type = AB;	break;
		case FSUBS:	func = fsubs;	type = AB;	break;
		case FADDS:	func = fadds;	type = AB;	break;
		case FSQRTS:	func = fsqrts;	type = AB;	break;
		case FRES:	func = fres;	type = AB;	break;
		case FMULS:	func = fmuls;	type = AC;	break;
		case FMSUBS:	func = fmsubs;	type = ABC;	break;
		case FMADDS:	func = fmadds;	type = ABC;	break;
		case FNMSUBS:	func = fnmsubs;	type = ABC;	break;
		case FNMADDS:	func = fnmadds;	type = ABC;	break;
		default:
			goto illegal;
		}
		break;

	case OP63:
		if (insn & 0x20) {
			switch ((insn >> 1) & 0x1f) {
			case FDIV:	func = fdiv;	type = AB;	break;
			case FSUB:	func = fsub;	type = AB;	break;
			case FADD:	func = fadd;	type = AB;	break;
			case FSQRT:	func = fsqrt;	type = AB;	break;
			case FSEL:	func = fsel;	type = ABC;	break;
			case FMUL:	func = fmul;	type = AC;	break;
			case FRSQRTE:	func = frsqrte;	type = AB;	break;
			case FMSUB:	func = fmsub;	type = ABC;	break;
			case FMADD:	func = fmadd;	type = ABC;	break;
			case FNMSUB:	func = fnmsub;	type = ABC;	break;
			case FNMADD:	func = fnmadd;	type = ABC;	break;
			default:
				goto illegal;
			}
			break;
		}

		switch ((insn >> 1) & 0x3ff) {
		case FCMPU:	func = fcmpu;	type = XCR;	break;
		case FRSP:	func = frsp;	type = XB;	break;
		case FCTIW:	func = fctiw;	type = XB;	break;
		case FCTIWZ:	func = fctiwz;	type = XB;	break;
		case FCMPO:	func = fcmpo;	type = XCR;	break;
		case MTFSB1:	func = mtfsb1;	type = XCRB;	break;
		case FNEG:	func = fneg;	type = XB;	break;
		case MCRFS:	func = mcrfs;	type = XCRL;	break;
		case MTFSB0:	func = mtfsb0;	type = XCRB;	break;
		case FMR:	func = fmr;	type = XB;	break;
		case MTFSFI:	func = mtfsfi;	type = XCRI;	break;
		case FNABS:	func = fnabs;	type = XB;	break;
		case FABS:	func = fabs;	type = XB;	break;
		case MFFS:	func = mffs;	type = X;	break;
		case MTFSF:	func = mtfsf;	type = XFLB;	break;
		default:
			goto illegal;
		}
		break;

	default:
		goto illegal;
	}

	switch (type) {
	case AB:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 16) & 0x1f];
		op2 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		break;

	case AC:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 16) & 0x1f];
		op2 = (void *)&current->thread.fpr[(insn >>  6) & 0x1f];
		break;

	case ABC:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 16) & 0x1f];
		op2 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		op3 = (void *)&current->thread.fpr[(insn >>  6) & 0x1f];
		break;

	case D:
		idx = (insn >> 16) & 0x1f;
		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
		break;

	case DU:
		idx = (insn >> 16) & 0x1f;
		if (!idx)
			goto illegal;

		sdisp = (insn & 0xffff);
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)(regs->gpr[idx] + sdisp);
		break;

	case X:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		break;

	case XA:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 16) & 0x1f];
		break;

	case XB:
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		break;

	case XE:
		idx = (insn >> 16) & 0x1f;
		if (!idx)
			goto illegal;

		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)(regs->gpr[idx] + regs->gpr[(insn >> 11) & 0x1f]);
		break;

	case XEU:
		idx = (insn >> 16) & 0x1f;
		op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
		op1 = (void *)((idx ? regs->gpr[idx] : 0)
				+ regs->gpr[(insn >> 11) & 0x1f]);
		break;

	case XCR:
		op0 = (void *)&regs->ccr;
		op1 = (void *)((insn >> 23) & 0x7);
		op2 = (void *)&current->thread.fpr[(insn >> 16) & 0x1f];
		op3 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		break;

	case XCRL:
		op0 = (void *)&regs->ccr;
		op1 = (void *)((insn >> 23) & 0x7);
		op2 = (void *)((insn >> 18) & 0x7);
		break;

	case XCRB:
		op0 = (void *)((insn >> 21) & 0x1f);
		break;

	case XCRI:
		op0 = (void *)((insn >> 23) & 0x7);
		op1 = (void *)((insn >> 12) & 0xf);
		break;

	case XFLB:
		op0 = (void *)((insn >> 17) & 0xff);
		op1 = (void *)&current->thread.fpr[(insn >> 11) & 0x1f];
		break;

	default:
		goto illegal;
	}

	eflag = func(op0, op1, op2, op3);

	if (insn & 1) {
		regs->ccr &= ~(0x0f000000);
		regs->ccr |= (__FPU_FPSCR >> 4) & 0x0f000000;
	}

	trap = record_exception(regs, eflag);
	if (trap)
		return 1;

	switch (type) {
	case DU:
	case XEU:
		regs->gpr[idx] = (unsigned long)op1;
		break;

	default:
		break;
	}
#endif /* CONFIG_MATH_EMULATION */

	regs->nip += 4;
	return 0;

illegal:
	return -ENOSYS;
}